[PATCH] net: exit immediately when encounter ipv6 fragment in skb_checksum_setup_ipv6()

[Miaohe Lin]

skb_checksum_setup_ipv6() always return -EPROTO if ipv6 packet is fragment.
So we should not continue to parse other header type in this case. Also
remove unnecessary local variable 'fragment'.

Signed-off-by: Miaohe Lin <linmia...@huawei.com>
---
 net/core/skbuff.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index c3496bd8e99e..4dc92290becd 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -4894,11 +4894,9 @@ static int skb_checksum_setup_ipv6(struct sk_buff *skb, 
bool recalculate)
        u8 nexthdr;
        unsigned int off;
        unsigned int len;
-       bool fragment;
        bool done;
        __sum16 *csum;
 
-       fragment = false;
        done = false;
 
        off = sizeof(struct ipv6hdr);
@@ -4956,8 +4954,11 @@ static int skb_checksum_setup_ipv6(struct sk_buff *skb, 
bool recalculate)
 
                        hp = OPT_HDR(struct frag_hdr, skb, off);
 
-                       if (hp->frag_off & htons(IP6_OFFSET | IP6_MF))
-                               fragment = true;
+                       /* Exit immediately when encounter ipv6 fragment. */
+                       if (hp->frag_off & htons(IP6_OFFSET | IP6_MF)) {
+                               err = -EPROTO;
+                               goto out;
+                       }
 
                        nexthdr = hp->nexthdr;
                        off += sizeof(struct frag_hdr);
@@ -4970,8 +4971,7 @@ static int skb_checksum_setup_ipv6(struct sk_buff *skb, 
bool recalculate)
        }
 
        err = -EPROTO;
-
-       if (!done || fragment)
+       if (!done)
                goto out;
 
        csum = skb_checksum_setup_ip(skb, nexthdr, off);
-- 
2.19.1